In situ forming hemostatic foam implants

A method of treating a patient by forming a polymer foam within a body cavity of the patient to control movement of a bodily fluid, comprising:

• placing a synthetic hydrophobic material into a body cavity of a living subject;
• foaming the hydrophobic polymer material while within the body cavity to form a foam;
• and
• limiting movement of a bodily fluid with the foam relative to an amount of movement of bodily fluid that would occur in the absence of the foam;
• wherein the step of foaming the hydrophobic polymer material comprises reaction of the hydrophobic polymer material with the water of a water-containing environment within the body cavity, wherein the reaction includes the generation of CO2 gas, said CO2 gas expanding the hydrophobic polymer material more than 12-fold and forcing the hydrophobic polymer material into an interstitial area of the body cavity.